Garmin GNC 420, Pilot'S Manual & Reference

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GNC 420(A) Pilot’s Guide and Reference 11-28
SECTION 11
ADDITIONAL FEATURES
190-00140-20 Rev. K
NOTe: Textual MeTars can only be requested
by identifier or by flight plan (if the flight plan
contains a MeTar station identifier).
•
Center - This field allows the pilot to specify
reference points for the request. The following
five options are available for the ‘Center’ field:
♦
Current Position - Request METAR data from
the aircraft’s current position.
♦
Look Ahead - Request METAR data ahead of
(along) the current route.
♦
From ID - Request NEXRAD data from a
specific waypoint identifier. If ‘From ID’ is
selected as the reference point for the request,
the ‘WPT’ field is displayed (in place of
‘Position’). The ‘WPT’ field is used to enter a
waypoint identifier as the reference point for
the request.
♦
From Lat/Lon - Request NEXRAD data from
a specific latitude and longitude. This is only
selectable when requesting from the map. The
‘Position’ field displays the position of the map
cursor and cannot be edited.
♦
From Flight Plan - Request METAR data from
one of the waypoints in the active flight plan.
This is only selectable when an active Flight
Plan has been selected. The ‘Flight Plan’ field
(displayed in place of ‘Position’) is used to select
which waypoint in the active flight plan to use
as the reference point for the request.
•
Radius (Graphical requests only) - This field
selects a request radius from 50 to 250 nm from
the selected position.
•
Position (also WPT or Flight Plan) - ‘Current
Posn’-Position is current, ‘Look Ahead’-Position is
look ahead position. ‘From ID’-Position is from
the ID entered into the WPT field. ‘Flight Plan’ is
the ID selected from the active flight plan.
•
Auto Request (GDL 49 Only) - This field is
used to set the time interval for the GDL 49 to
automatically send a NEXRAD data request. The
time options are OFF, 10 min, 15 min, 20 min, 30
min, 45 min, and 1 hour. When an auto request
time is selected, the first request is sent after the
specified time has elapsed from when the field
was set (as opposed to immediately sending a
request).
NOTe: it is recommended that the pilot turn the
auto request function ‘on’ by setting it to ‘10 min’
updates. This setting provides best performance
for the GDL 49.
•
The ‘Manual Send?’(GDL 49) or ‘Update Request?’
(GDL 69) field is used to request METAR Data.
4) Use the small and large right knobs to select
the desired data and the
ENT
Key to enter the
data into the appropriate fields on the METAR
Request Page.
5) Select ‘Manual Send?’ or ‘Update Request?’
and press the ENT Key. The request has been
sent. Note that selecting ‘Auto Request’
and pressing the
ENT Key does not send the
request until after the auto time period.
6) To exit from the NEXRAD Request Page, press
the small
right
knob. The Data Link Page is
displayed.